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<li class="level1"><a href="#public-functions">公用函数</a></li>
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<h1 class="title">QQuickImageResponse 类</h1>
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<p>The <a href="qquickimageresponse.html">QQuickImageResponse</a> class provides an interface for asynchronous image loading in <a href="qquickasyncimageprovider.html">QQuickAsyncImageProvider</a>. <a href="#details">更多...</a></p>
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<tr><td class="memItemLeft rightAlign topAlign">头文件：</td><td class="memItemRight bottomAlign">   <span class="preprocessor">#include &lt;QQuickImageResponse&gt;</span>
</td></tr><tr><td class="memItemLeft rightAlign topAlign"> qmake:</td><td class="memItemRight bottomAlign"> QT += quick</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Since:</td><td class="memItemRight bottomAlign">  Qt 5.6</td></tr><tr><td class="memItemLeft rightAlign topAlign">继承自：</td><td class="memItemRight bottomAlign"> <a href="../qtcore/qobject.html">QObject</a></td></tr></table></div><ul>
<li><a href="qquickimageresponse-members.html">所有成员的列表，包括继承成员</a></li>
<li><a href="qquickimageresponse-obsolete.html">废弃的成员</a></li>
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<h2 id="public-functions">公用函数</h2>
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<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qquickimageresponse.html#QQuickImageResponse">QQuickImageResponse</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual </td><td class="memItemRight bottomAlign"><b><a href="qquickimageresponse.html#dtor.QQuickImageResponse">~QQuickImageResponse</a></b>() override</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual QString </td><td class="memItemRight bottomAlign"><b><a href="qquickimageresponse.html#errorString">errorString</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual QQuickTextureFactory *</td><td class="memItemRight bottomAlign"><b><a href="qquickimageresponse.html#textureFactory">textureFactory</a></b>() const = 0</td></tr>
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<li class="fn">31 个公用函数继承自<a href="../qtcore/qobject.html#public-functions">QObject</a></li>
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<h2 id="public-slots">公用槽函数</h2>
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<tr><td class="memItemLeft rightAlign topAlign"> virtual void </td><td class="memItemRight bottomAlign"><b><a href="qquickimageresponse.html#cancel">cancel</a></b>()</td></tr>
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<li class="fn">1 个公用槽函数继承自<a href="../qtcore/qobject.html#public-slots">QObject</a></li>
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<h2 id="signals">信号</h2>
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<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qquickimageresponse.html#finished">finished</a></b>()</td></tr>
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<li class="fn">2 个信号继承自<a href="../qtcore/qobject.html#signals">QObject</a></li>
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<h2 id="static-public-members">静态公用成员</h2>
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<tr><td class="memItemLeft rightAlign topAlign"> const QMetaObject </td><td class="memItemRight bottomAlign"><b><a href="qquickimageresponse.html#staticMetaObject-var">staticMetaObject</a></b></td></tr>
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<li class="fn">9 个静态公用成员继承自<a href="../qtcore/qobject.html#static-public-members">QObject</a></li>
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<h3>额外的继承成员</h3>
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<li class="fn">1 个属性继承自<a href="../qtcore/qobject.html#properties">QObject</a></li>
<li class="fn">9 个保护函数继承自<a href="../qtcore/qobject.html#protected-functions">QObject</a></li>
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<!-- $$$QQuickImageResponse-description -->
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<h2 id="details">详细信息</h2>
<p>The <a href="qquickimageresponse.html">QQuickImageResponse</a> class provides an interface for asynchronous image loading in <a href="qquickasyncimageprovider.html">QQuickAsyncImageProvider</a>.</p>
<p>The purpose of an image response is to provide a way for image provider jobs to be executed in an asynchronous way.</p>
<p>Responses are deleted via <a href="../qtcore/qobject.html#deleteLater">deleteLater</a> once the <a href="qquickimageresponse.html#finished">finished</a>() signal has been emitted. If you are using <a href="../qtcore/qrunnable.html">QRunnable</a> as base for your <a href="qquickimageresponse.html">QQuickImageResponse</a> ensure automatic deletion is disabled.</p>
<p>See the <a href="qtquick-imageresponseprovider-example.html">Image Response Provider Example</a> for a complete implementation.</p>
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<p><b>请参考 </b><a href="qquickimageprovider.html">QQuickImageProvider</a>。</p>
<!-- @@@QQuickImageResponse -->
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<h2>成员函数文档</h2>
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<h3 class="fn" id="QQuickImageResponse"><a name="QQuickImageResponse"></a>QQuickImageResponse::<span class="name">QQuickImageResponse</span>()</h3>
<p>Constructs the image response</p>
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<h3 class="fn" id="dtor.QQuickImageResponse"><a name="dtor.QQuickImageResponse"></a><code>[override virtual] </code>QQuickImageResponse::<span class="name">~QQuickImageResponse</span>()</h3>
<p>Destructs the image response</p>
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<!-- $$$cancel[overload1]$$$cancel -->
<h3 class="fn" id="cancel"><a name="cancel"></a><code>[virtual slot] </code><span class="type">void</span> QQuickImageResponse::<span class="name">cancel</span>()</h3>
<p>This method is used to communicate that the response is no longer required by the engine.</p>
<p>It may be reimplemented to cancel a request in the provider side, however, it is not mandatory.</p>
<p>A cancelled <a href="qquickimageresponse.html">QQuickImageResponse</a> still needs to emit <a href="qquickimageresponse.html#finished">finished</a>() so that the engine may clean up the <a href="qquickimageresponse.html">QQuickImageResponse</a>.</p>
<p><b>Note: </b><a href="qquickimageresponse.html#finished">finished</a>() should not be emitted until the response is complete, regardless of whether or not cancel() was called. If it is called prematurely, the engine may destroy the response while it is still active, leading to a crash.</p><!-- @@@cancel -->
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<h3 class="fn" id="errorString"><a name="errorString"></a><code>[virtual] </code><span class="type"><a href="../qtcore/qstring.html">QString</a></span> QQuickImageResponse::<span class="name">errorString</span>() const</h3>
<p>Returns the error string for the job execution. An empty string means no error.</p>
<!-- @@@errorString -->
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<h3 class="fn" id="finished"><a name="finished"></a><code>[signal] </code><span class="type">void</span> QQuickImageResponse::<span class="name">finished</span>()</h3>
<p>Signals that the job execution has finished (be it successfully, because an error happened or because it was cancelled).</p>
<p><b>Note: </b>Emission of this signal must be the final action the response performs: once the signal is received, the response will subsequently be destroyed by the engine.</p><!-- @@@finished -->
<!-- $$$textureFactory[overload1]$$$textureFactory -->
<h3 class="fn" id="textureFactory"><a name="textureFactory"></a><code>[pure virtual] </code><span class="type"><a href="qquicktexturefactory.html">QQuickTextureFactory</a></span> *QQuickImageResponse::<span class="name">textureFactory</span>() const</h3>
<p>Returns the texture factory for the job. You can use <a href="qquicktexturefactory.html#textureFactoryForImage">QQuickTextureFactory::textureFactoryForImage</a> if your provider works with <a href="../qtgui/qimage.html">QImage</a>. The engine takes ownership of the returned <a href="qquicktexturefactory.html">QQuickTextureFactory</a>.</p>
<p><b>Note: </b>This method will be called only when needed. For example, it may not be called if there is an error or the job is cancelled. Therefore, allocate the <a href="qquicktexturefactory.html">QQuickTextureFactory</a> instance only in this method or otherwise ensure its deletion.</p><!-- @@@textureFactory -->
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